Patent GB-587566-A (GB)
Title: Improvements in or relating to the forming of composite ester bodies
IPC: C09D167/08
Filed: 1943-01-09
Abstract: Composite ester bodies formed from reaction of two different acid bodies with a single polyhydric alcohol, e.g., drying oil-natural varnish resin composites or synthetic resin, fatty acid or drying oil modified alkyd resins are prepared by heating the reactants directly at atmospheric pressure to boiling point in the presence of an organic solvent which, alone, boils above 220 DEG F. and which is present throughout the reaction in 2-15 per cent. of the weight of reacting material so that the vapourizing solvent agitates the mass of material and forms a solution which boils above 380 DEG F. and at least 60 DEG F. above the boiling point of the pure solvent, the solvent which leaves the reaction mass being condensed, separated from entrained water, and returned to the reaction zone.  Preferably the reaction is performed under reflux condenser, condensate collecting in a trap for water, the water from the reaction displacing solvent from the trap back to the reaction zone.  The amount of water collected forms a measure of the course of the reaction.  Solvents which may be used are "Solvesso" (R.T.M.), mineral spirits, V.M. and P. naphtha, xylol, toluol or high-flash naphtha.  In an example rosin, chinawood oil, lime, litharge and a small proportion of mineral spirits are heated to 585 DEG F. for about 15 minutes.  More mineral spirits are then added to thin the products.  Reference has been directed by the Comptroller to Specification 543,254.ALSO:Composite ester bodies formed from reaction of two different acid bodies with a single polyhydric alcohol, e.g. drying oil-natural resin varnishes, or drying oil-modified alkyd resins, are formed by heating the ingredients directly in a vessel at substantially atmospheric pressure to boiling point in the presence of an organic solvent which, alone, boils above 220 DEG  F. and boils actively below 400 DEG  F. and which is present throughout the reaction in 2-15 per cent of the weight of reacting materials so that the vaporizing solvent agitates the mass of material and forms a solution which boils above 380 DEG  F. and at least 60 DEG  F. above the temperature at which the pure solvent boils actively, the solvent which leaves the reaction mass being condensed, separated from entrained water and returned to the reaction mass. Some of the added solvent is introduced in the water trap included in the condensing system and is displaced by condensed water to return to the reaction zone.  The invention is illustrated by reference to a 25-gallon varnish prepared from oil-soluble phenolic resin, chinawood oil, linseed oil and solvents such as "Solvesso," mineral spirits, turpentine, V.M. and P. naphtha. Other suitable solvents are xylol, toluol and high-flash naphtha. In examples: (1) a varnish was prepared from the ester gun modified phenol-formaldehyde resin known under the Registered Trade Mark "Beckacite," rosin, litharge, chinawood oil, bodied linseed oil, "Solvesso No. 3," by heating them in a kettle at 525 DEG  F. until the desired viscosity was reached.  The mixture was then cooled and turpentine and mineral spirits (B.P. about 350 DEG  F.) were added. An enamel was prepared by mixing the varnish with zinc oxide, Titanox, and a cobalt drier solution.  (2) An alkyd resin was prepared from glycerol, phthalic anhydride, linseed fatty acids and a minor proportion of "Solvesso No. 3," at a temperature of about 480 DEG  F.  The linseed oil fatty acids may be replaced by fish oil fatty acids known as Neo-fat 19, or may be partly replaced by an oil-soluble phenolic resin known under the Registered Trade Mark "Para-Dura-10 P."  The glycerine and phthalic anhydride were partially reacted at about 370 DEG  F. in presence of the solvent before the modifying agents were introduced.  The amount of water liberated during the reaction controls the amount of solvent displaced to return to the reaction zone and also affords a means for following the course of the reaction.  (3) Glycerine, phthalic anhydride, maleic anhydride and linseed fatty acid were heated to 480 DEG  F. with a minor proportion of "Solvesso No. 3."  The cooled product was thinned with mineral spirits.  (4) Castor oil and glycerine were heated together to 520 DEG  F., cooled to 440 DEG  F. and the glycerol and phthalic anhydride then added with a small amount of xylol, and the mixture again heated to 480 DEG  F.  The resin product was thinned with more xylol.  The amount of water liberated during the second stage of the process indicated that the castor oil was partially dehydrated.  (5) Perilla oil, tung oil and glycerol were heated with lead oxide to 440 DEG  F.  Phthalic anhydride and a rosin-modified phenolic resin known under the Registered Trade Mark "Bakelite" XR2963 and a little "Solvesso No. 2" were added and the mixture heated to 430 DEG  F.  The product was thinned with mineral spirits.  (6) Tung oil, linseed oil, glycerol and lead oxide were heated to 440 DEG  F.  Phthalic anhydride, a maleic-modified ester gum known as "801 Amberol" and a small proportion of "Solvesso No. 2" were added and the mixture heated to 420 DEG  F.  The product was thinned with "Solvesso No. 2."  (7) A dehydrated castor oil-modified glycerol phthalate resin was similarly prepared in presence of a small quantity of xylol, and a soya bean oil-modified glycerol phthalate resin in presence of a small quantity of "Solvesso No. 2," zinc oxide being used in place of lead oxide to aid the initial alcoholysis of the soya bean oil and glycerol.  Other oils which may be employed are rapeseed, hempseed, oiticica, coconut, safflower, sunflower or poyoate.  The corresponding fatty acids may also be employed, oil-soluble resins employed in the above examples may be replaced by natural resins, rosin, limed rosin, zinced rosin, ester gum, or ester gum-modified phenol-formaldehyde resins.  Lead, cobalt, manganese, iron, calcium or zinc may be introduced as oxides, hydroxides, carbonates, acetates, resinates or naphthenates. Phthalic anhydride may be replaced by sebacic, adipic or maleic adducts, or by succinic anhydride or fumaric acid, if ethylene glycol, diethylene glycol, triethylene glycol or propylene glycol are present with the glycerol.  Pentaerythritol, mannitol or sorbitol may be used instead of glycerol.  Reference has been directed by the Comptroller to Specification 543,254.